magma:// Please install CHIMP (https://github.com/edgarcosta/CHIMP) if you want to run this code
chi := DirichletCharacter("1332.121");
S:= CuspForms(chi, 2);
N := Newforms(S);
sage:from sage.modular.dirichlet import DirichletCharacter
H = DirichletGroup(1332, base_ring=CyclotomicField(6))
chi = DirichletCharacter(H, H._module([0, 2, 4]))
N = Newforms(chi, 2, names="a")
This newform subspace can be constructed as the kernel of the linear operator
\( T_{5}^{37} - 3 T_{5}^{36} - 112 T_{5}^{35} + 329 T_{5}^{34} + 5664 T_{5}^{33} - 16373 T_{5}^{32} + \cdots + 4304016 \)
acting on \(S_{2}^{\mathrm{new}}(1332, [\chi])\).